Climate Overshoot

From Open Risk Manual

Definition

Climate Overshoot refers to a period during which Global Warming will have increased past 1.5° C, before it is projected to fall back down due to the results of Climate Change Mitigation. [1],[2]

  • Limited Overshoot refers to exceeding 1.5°C global warming by up to about 0.1°C and for up to several decades.
  • High Overshoot refers to temporarily exceeding 1.5°C global warming by 0.1-0.3°C for up to several decades

Context

Under the Paris Agreement, countries are expected to take the necessary measures to avoid dangerous climate change by limiting global warming to well below 2°C and pursuing efforts to limit it to 1.5°C. But even best-case scenarios now indicate a significant chance of overshooting these goals, even if temporarily. This period will probably occur around the middle of this century but troubling signs are emerging that it may occur even earlier.

Implications

The longer the climate overshoot lasts, the more dangerous the world will become. A prolonged period of higher global temperatures will have devastating and irreversible impacts on natural ecosystems, biodiversity, and human communities, particularly in dry areas, coastal zones, and other vulnerable locations. Making deep emission cuts during this decade is of extreme importance to limiting the duration and impacts of the climate overshoot.

Futher Resources

References

  1. The Climate Dictionary, UNDP, 2023
  2. IPCC, Climate Change 2022, Mitigation of Climate Change